Improvement in sewing-machines



lView.

. B', which is connected to-the head C.

UNITED STATES PATENT EEicE.

NV. A. MACK, OF CLEVELAND. CHIC.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 45,059, dated November15, 1864.

description of the construction and operation of the saine, referencebeing had to the accompanying drawings, making a part ot' thisspecitication, in which- Figure 1 is a side view ofthe machine. Fig.`

2 is a View ofthe under side. Fig. 3 is an end Figs. el, 5, 6, and 7represent detached sections.

Like letters of reference denote like parts in the ditt'erent views.

My improvement relates to the manner of carrying the shuttle, inconnection with the shuttle-race, to the construction ot the shuttle inrelation to giving the desired tension to the lower thread, and also tothe manner of giving tension tothe upper thread from the spool.

A is the platform or bed-plate of the inachine, near one end of which isthe standard B, that curves round, forming a horizontal arm, rEhis headforms a case for thecrank-wheel C", ncedle-bar D, and pressure-bar E, asindicated by -the dotted lines in Fig.'3. rIhe crank-Wheel C issecuredto the end of the shaft that extends through Ithe arm B', and isconnected with the driving-wheelaC", which operates the -needle-bar,there being a wrist, c, on the crank-4 On the under side of thebed-plate F is theprimary, and G the secondary, feed-wheels on the shaftG', one end'of which is supported by an arm, f, secured to thebed-plate, and 'theend on which is the primary feed-wheel rests in anadjustable bearing, g, which is secured in place by a screw, g', in aslot of an arm. or

` lug,j", fastened to the bed-plate,

His a vibrating arm or lever pivoted at HQ. The 'end I holds theshuttle, and the other end is inserted in a hole in the head ot' thesocket or thimble H'", Fig. 1. This socket receives the pendent end ofthe lever u, which. vibrates upon the stud u by the action ot' the cam'v upon the driving-shaft; The upper end, wf, of the lever is forked, soas to receive the cam between the forks. The vibration ot' the lever uis transmitted to the larm H by its con nection. As the lever u tits"loosely in the socket, so that the socket may turn, and also slide upand down on the end ot' the leverar, forming a compensating-joint, thisallows the leveru and arm H to be readily adjusted to each other in thcvarious positions assumed when in operation. The shuttle end ot' the armH branches out, and is formed into a head or holde1,l,in which theshuttle H rests, and is carried back and forth. (Represented in Figs. 2,4, and 5.) Fig. 4 is a view at the end of the bed-plate underneath the`needle and pressure bars, with the adjustable plates A removed, showingthe top of the shuttle as it is held in the holder close to theshuttle-race J. (Represented also in Fig. 5.)

lhe holder is formed with end pieces,ft' t', between which is aninclined plane, (indicated by the dotted line L in Fig. 5,) on which theshuttle rests, that,together with the end pieces and in connection withthe shuttle-race .lbkeeps the shuttle from tnovingr in the holder andretains it in the required position as it is being operated. i

The shuttle-raced consists ot` a polished rnetallic piece, forming thesegment-.of a circle, the face of which is at right angles to the planeof the vibrating arni, vertical on both sides, and extends up close tothe plates A. inside of the feed-wheel F, with a needle-slot, d, throughthe center, the ends being secured to'lugs lf* onthe bed-plate. rlheshuttle is so formed that it fits close to the race J trom the heel tothe peint the whole' length ot' its movement, and as it is stationary inthe holder and its weight entirely supported by the vibrating arm, and"only one side moving against the race, very littlefriction is produced-Thisarrangement is in every way an' improvement over the man,- ner ofvibrating the shuttle in my former patent, in whichthe shuttle is movedbach and fortlrin an angular trough, forming the shut` tlc-race. Theshuttle thus moving produces friction'l and wears it away ontheroutside, and its surface is apt to be roughened by its weightresting and rubbing on lthe angular trough, which is liable to chai'eand cut the thread in forming the stitch. The trough admits ot' anaccumulation of dust and dirt, causing the machine to operate with lessfacility, and it cannot be so easily cleaned, nor the shuttle taken outand put in, as readily as with my improvement.

The shuttle is differently constructed in regard to adjusting thetension ot' the thread. ln place ot' a rib upon the upper margin, withholes through which the thread is laced, there is an adjustable spring.u, (seen in Figs. 4 and 6,) along the top ot' the shuttle close to theshuttle-race, one end ot' which is put through nn opening or hole, o, inthe shuttle, andthe other end is fastened in at the heel erd oftheshuttle by the screw N, which has a groove, n', round the shoulder, intowhich the end of the spring passes as the heel ot the shuttle is closedby the screw shown in Fig. (i, which is a section ofthe shuttle. Thespring is'thus retained in place on the shuttle with hot-h ends i'ree,giving elasticity to, the spring, and by means ot" which it can beadjusted. The screw N forms a bearing for one end of the bobbin L, theother end turning in the solid end of the shuttle, as represented.Thepthread from the bobbin passes through an opening, 1, in the shuttlealongside or under the spring, through holes in the spring, as in Figs.4 and 6, the thread being laced through two or more holes, as may berequired to produce thedesired tension. As the spring is notrigidlyfastened at either end, it yields readily to the unevenness of' thethread, producing a most even and unii'orm tension, and it is likewiseperfectly adapted to dii'terentsized threads, coarse or iine, withoutany change ot' setting.

'lhe tension ot' the upper thread from the spool in connection with theneedleis regulated by a spring, M, arranged above the arm B about themiddle, secured to the bracket m by a screw, m. A perspective view ofthis spring isisecn in Fig. 7, representing a tiat piece bent togetherat the two ends, forming a tlat point, p, and it is kept iu that .formon the bracket m by the screw m.

Near the point, through the upper part of the piece forming the spring,is a hole, 1', through which the thread from the spool Q is put andpassed between the ends forming the point of the spring, as indicated bythe red line p', and by which the thread is regulated, as it is drawnfrom lthe spool, in the most uniform manner, and from theelasticity ofthe spring i t is equally well adapted to various-sized threads, so thatthe thread may be changed withoutremoving the screw and changing thespring, the same spring as adjusted being perfectly adapted to give thedesired tension to any sized thread. The thread extends through theguide q and through the top ot' the needlebar down through the guide tand spring t on the outside ofthe headC. as noted by the lred line inFig. 3, the spring t taking up the loose thread from'the needle.. Thesedevices altogether, n1 giving tension to the thread and taking up theloose thread from the needle, regulate the thread in the most uniformand perfect manner.

What I claim as my improvement, and desire to secure by Letters Patent,is-

1. The arrangement ot' the shuttle-holder I, race J', and shuttle 1I',in combination with the vibrating arm H', socket H", lever u, and cam c,constructed and operating as and for the purpose set forth.

2. The vspring fn, in combination with the screw N and shuttle, as andfor the .purpose described.

W'. A. MACK.

